ANALYSIS MODELS OF INITIAL COMPRESSION AND RECOMPRESSION CURVES OF SOILS
CAO Wengui1，LI Peng1，2，ZHANG Chao1，ZHANG Yongjie3
(1. Institute of Geotechnical Engineering，Hunan University，Changsha，Hunan 410082，China；2. Hunan Expressway Administration Bureau，Changsha，Hunan 410001，China；3. School of Civil Engineering and Architecture，Changsha University of Science and Technology，Changsha，Hunan 410014，China)
Abstract：The relationship between the void ratio and compressive stress of soils under initial compression and recompression，namely e-p curve，is a key issue for the analysis of natural ground settlement. Firstly，a hyperbolic formula between the compression stress and strain for soils was introduced based on the investigation of the mechanism of initial deformation of compression and the characteristics of e-p curves for soils. The mathematical relationships to determine the parameters of the formula were derived assuming that the soils were under consolidation with lateral restraint. The difference between the e-p compression curves for initial compression and recompression soils lies in the different values of initial void ratios and initial compression modulus for each case. A method to determine the parameters，such as the initial void ratio and the compression modulus of soils at recompression，was proposed. A formula of e-p curve for recompression of soil considering the effect of stress history was put forward. The proposed formulae of e-p curve for initial compression and recompression of soils have three conventional parameters，the initial void ratio and the initial compression modulus and the compression coefficient. Results of comparisons show that the experimental data and theoretical curves are in good agreement.
2015, Vol. 34 
